weak signal modes in amateur radio
DESCRIPTION
Presentation to the Milford Amateur Radio Club on weak signal modes, specifically JT-65, WSPR, and QRSS.TRANSCRIPT
Weak Signal Modes
Andrew Rohne AC8JOFebruary 9, 2012
Three Part Presentation
JT65WSPRQRSS
JT65 and WSPR
Both by Joe Taylor, PhD K1JTAstrophysicist at PrincetonNobel Prize in Physics 1993
Time sync CRITICALLong TX and RX sequencesWeak signal - use low power
JT65
Originally for EME on HF and VHFThree Submodes
JT65A ~> HF and 6mJT65B ~> 2m and 70cmJT65C ~> 23cm
Short, to-the-point QSOs
Less sensitive More resistant to libration fading & frequency drift
JT65
13 Characters onlyNot a ragchew mode! Allows for signal report and 73
only53 second TX/RX SequencesHF Skywave ~> JT65-HF
JT65-HF Software
JT65 QSO (with N1FIY)
N1FIY AC8JO EM79
N1FIY AC8JO R-09
N1FIY AC8JO 73
JT65 post-QSO
JT65 QSO
CQ K1JT FN20K1JT W6DTW CM97W6DTW K1JT -18K1JT W6DTW R-16W6DTW K1JT RRRK1JT W6DTW 73W6DTW K1JT 73
(QSO Stolen from NW7US.US/jt65a.html)
WSPR
Weak Signal Propagation ReporterNot a QSO ModeTransmits call+grid2 Min TX/RX SequencesClock important!WSPRNet.org
WSPR Software
WSPRNet.org (Spotting)
Spotting Map
Spotted!
206 mi per watt
Spotted Map
QRSS
Super Slow CW“Normal” or FSKCWHellschreiber has been used
Not a QSO mode
Software
QuickTime™ and a decompressor
are needed to see this picture.
Website - “Pensacola Snapper”
Conclusion
JT-65WSPRQRSS
Andrew Rohne AC8JOwww.ac8jo.us